This training and research award will prepare the candidate for an independent career as a molecular and behavioral neuroscientist using rigorous behavioral testing and genetic manipulations to analyze the brain circuits underlying learning and memory. The candidate is an experimental psychologist with significant experience in the area of animal learning. Training provided under the award take place at Columbia University's Departments of Psychiatry and Neuroscience and will enable the candidate to (1) develop laboratory skills in molecular genetics and quantitative microscopy;(2) expand his knowledge of molecular genetics and translational neuroscience so that he can independently develop novel scientific ideas, integrate his research findings with existing knowledge, and relate them to clinical practice;(3) receive mentorship in professional development;and (4) develop a strong understanding of the ethical issues inherent in the practice of science. The training goals will be accomplished through a program combining practical training, formal mentorship, and consultations with experienced independent researchers, coursework, seminar attendance, and professional scientific meetings. The research supported under the award will elucidate mechanisms through which adult hippocampal neurogenesis contributes to learning and memory. The adult hippocampus retains the ability to generate neurons, and a rapidly growing literature documents that adult-born neurons are functionally significant. The candidate has shown, for instance, that blocking hippocampal neurogenesis using irradiation or an inducible genetic method impairs contextual fear conditioning, a ubiquitous form of learning in which organisms acquire fear of environments that predict harm. Using contextual fear conditioning as a model system, the proposed research will use targeted irradiation and genetic manipulations to analyze how adult-born neurons contribute to acquisition, retention, and retrieval of memories. The proposed research will develop new tools for studying the role of adult-born neurons in learning and behavior, further our understanding of the biology of memory, and may give insight into how alterations in neurogenesis contribute to the etiology or treatment emotional disorders.